Alcoholic Liver Disease (ALD) remains a leading cause of liver-related deaths in the U.S., and there is still no FDA-approved therapy. Abnormal cytokine metabolism is a major feature of ALD. Elevated serum concentrations of tumor necrosis factor (TNF) and TNF-inducible proinflammatory cytokines/chemokines, such as IL-8 and IL-18 have been reported in patients with alcoholic hepatitis and/or cirrhosis, and levels correlated with markers of the acute phase response, liver function, and clinical outcome. Similarly, there are depressed levels of the critical anti-inflammatory cytokine IL-10. Studies in animal models support an etiologic role for cytokines in the liver injury of ALD. The major problem to be investigated in this proposal is the mechanism(s) for this dysregulated cytokine metabolism, and our overall goal is the development of novel therapeutic interventions. ALD is associated with an increase in oxidative stress with a concomitant decrease in cellular antioxidants, such as glutathione (GSH) and importantly, S-adenosyl-L-methionine (SAM), due to subnormal synthesis. Clinical studies have suggested that SAM has beneficial effects in many hepatic disorders including ALD, and numerous animal studies have clearly demonstrated the protective effects of SAM against a variety of hepatotoxins. Previous studies from our group evaluated the role of SAM in positively modulating endotoxin (LPS)-stimulated TNF and IL-10 production related to ALD. We showed that SAM decreased LPS stimulated TNF production and increased LPS stimulated IL-10 production, and that SAM increased cellular levels of cyclic AMP (cAMP), which is known to positively modulate cytokine production. We therefore began an evaluation of the role of cAMP in dysregulated cytokine production in ALD, which is the research focus of this current proposal. We present compelling preliminary data that cAMP is decreased in a macrophage cell line chronically cultured in alcohol, and in Kupffer cells from mice chronically fed ethanol intragastrically. Our working hypothesis is that altered phosphodiesterase 4B (PDE4B) and cAMP metabolism cause abnormal TNF and IL-10 metabolism, which play a critical role in the development and perpetuation of ALD. Specific Objectives for this proposal are to: 1. Document increased PDE4B expression/activity and decreased cAMP in peripheral blood monocytes from patients with alcoholic hepatitis (AH) and alcoholic cirrhosis, and evaluate whether in vitro incubation of monocytes with specific phosphodiesterase inhibitors corrects dysregulated cAMP and cytokine metabolism;2. Determine whether PDE4 (and specifically, PDE4B) inhibition blocks the development of alcohol-induced liver injury in a murine intra-gastric ethanol-feeding model of chronic ALD and in a murine model of AH;3. Evaluate potential molecular and epigenetic mechanisms whereby cAMP metabolism is altered in alcoholic liver disease;and 4. Evaluate the effects of combined consumption of a commercially- available adenyl cyclase agonist (Misoprostol - increases cAMP production) and a phosphodiesterase inhibitor (Pentoxyfilline - decreases cAMP breakdown) in normal volunteers and in patients with stable alcoholic cirrhosis.

Public Health Relevance

Alcoholic Liver Disease (ALD) remains a leading cause of death from liver disease in the U.S. and there is still no FDA-approved therapy. Abnormal cytokine metabolism is a major feature of ALD. Elevated serum concentration levels of tumor necrosis factor (TNF) and TNF-inducible proinflammatory cytokines/chemokines, such as IL-8 and IL-18 have been reported in patients with alcoholic hepatitis and/or cirrhosis, and levels correlated with markers of the acute phase response, liver function, and clinical outcome. Similarly, there are depressed levels of the critical anti-inflammatory cytokine IL-10. Studies in animal models support an etiologic role for cytokines in the liver injury of ALD. The major problem to be investigated in this proposal is the mechanism(s) for this dysregulated cytokine metabolism, and our overall goal is the development of novel therapeutic interventions.

Agency
National Institute of Health (NIH)
Institute
National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Type
Research Project (R01)
Project #
5R01AA018869-05
Application #
8509554
Study Section
Special Emphasis Panel (ZAA1-JJ (06))
Program Officer
Radaeva, Svetlana
Project Start
2009-09-20
Project End
2014-08-31
Budget Start
2013-09-01
Budget End
2014-08-31
Support Year
5
Fiscal Year
2013
Total Cost
$366,862
Indirect Cost
$119,780
Name
University of Louisville
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
057588857
City
Louisville
State
KY
Country
United States
Zip Code
40292
Ghare, Smita S; Joshi-Barve, Swati; Moghe, Akshata et al. (2014) Coordinated histone H3 methylation and acetylation regulate physiologic and pathologic fas ligand gene expression in human CD4+ T cells. J Immunol 193:412-21
Shi, Xue; Wei, Xiaoli; Koo, Imhoi et al. (2014) Metabolomic analysis of the effects of chronic arsenic exposure in a mouse model of diet-induced Fatty liver disease. J Proteome Res 13:547-54
Liu, Yanlong; Ma, Zhenhua; Zhao, Cuiqing et al. (2014) HIF-1? and HIF-2? are critically involved in hypoxia-induced lipid accumulation in hepatocytes through reducing PGC-1?-mediated fatty acid ?-oxidation. Toxicol Lett 226:117-23
Watson, Walter H; Burke, Tom J; Doll, Mark A et al. (2014) S-adenosylhomocysteine inhibits NF-*B-mediated gene expression in hepatocytes and confers sensitivity to TNF cytotoxicity. Alcohol Clin Exp Res 38:889-96
Kharbanda, Kusum K; Bardag-Gorce, Fawzia; Barve, Shirish et al. (2013) Impact of altered methylation in cytokine signaling and proteasome function in alcohol and viral-mediated diseases. Alcohol Clin Exp Res 37:1-7
Smart, Laura; Gobejishvili, Leila; Crittenden, Neil et al. (2013) Alcoholic Hepatitis: Steroids vs. Pentoxifylline. Curr Hepat Rep 12:59-65
Wei, Xiaoli; Shi, Xue; Koo, Imhoi et al. (2013) MetPP: a computational platform for comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry-based metabolomics. Bioinformatics 29:1786-92
Kirpich, Irina A; Feng, Wenke; Wang, Yuhua et al. (2013) Ethanol and dietary unsaturated fat (corn oil/linoleic acid enriched) cause intestinal inflammation and impaired intestinal barrier defense in mice chronically fed alcohol. Alcohol 47:257-64
Bull-Otterson, Lara; Feng, Wenke; Kirpich, Irina et al. (2013) Metagenomic analyses of alcohol induced pathogenic alterations in the intestinal microbiome and the effect of Lactobacillus rhamnosus GG treatment. PLoS One 8:e53028
Song, Ming; Schuschke, Dale A; Zhou, Zhanxiang et al. (2013) Modest fructose beverage intake causes liver injury and fat accumulation in marginal copper deficient rats. Obesity (Silver Spring) 21:1669-75

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